Measurement of Regional Cerebral Blood Volume in Normal Rabbits on Perfusion-weighted MR Image

ABSTRACT

PURPOSE: To evaluate the usefulness of cerebral blood flow measurement applied to perfusion weighted image with short-scan time single shot gradient echo-planar technique in measuring cerebral blood volume(rCBV) of normal rabbits. MATERIALS AND METHODS: With 2.1-3.6 kg weighted rabbits, image is acquired when they are in supine position in children positioner. Perfusion weighted image is acquired to 44 seconds per 1 second successively. After 4 seconds later, Gd-DTPA 2ml are injected into int. jugular vein with 2 ml per second and normal saline is also injected after that. Same technique is applied 2 times per 30 minites in same rabbit. After Image is obtained in two part of cerebral cortex at vertex, convexity, in one of basal ganglia with choosing about 3-5mm2 areas. Curve of signal intensity changes in time sequence is drawn. After this images are transmitted by PC and software IDL, regional cerebral blood volume is measured with imaging processing program made by us. RESULTS: With 22 of 24 rabbits, satisfactory 1-2 signal intensity versus time curve is made. Cerebral blood capacity and contrast media stay time (ST) is measured in two cerebral cortex and basal ganglia refering in parietal cerebral cortex. Mean focal cerebral blood flow capacity ratio in cortex was 0.97+/-0.35 and in basal ganglia, 0.99+/-0.37, mean contrast media stay time in cortex was 9.83+/-1.63 sec and in basal ganglia, 9.42+/-1.14 sec, but there was no statistically significant difference between two areas (p=0.05). CONCLUSION: In cerebral cortex and basal ganglia, there is no difference in mean focal blood volume and mean contrast stay time. Therefore, PWI is useful in cerebral blood flow and early diagnosis, prognosis of cerebral ischemic disease. Hereafter, it is helpful in analysing cerebral blood flow changes with comparison difference in rCBV between normal tissue and ischemic tissue, and that with DWI finding in infarcted patient.